<?php
// +----------------------------------------------------------------------
// | ThinkPHP [ WE CAN DO IT JUST THINK IT ]
// +----------------------------------------------------------------------
// | Copyright (c) 2006-2014 http://thinkphp.cn All rights reserved.
// +----------------------------------------------------------------------
// | Licensed ( http://www.apache.org/licenses/LICENSE-2.0 )
// +----------------------------------------------------------------------
// | Author: liu21st <liu21st@gmail.com>
// +----------------------------------------------------------------------

namespace Think\Db\Driver;

use Think\Db\Driver;

/**
 * mysql数据库驱动
 */
class Mysql extends Driver
{

    /**
     * 解析pdo连接的dsn信息
     * @access public
     * @param array $config 连接信息
     * @return string
     */
    protected function parseDsn($config)
    {
        $dsn  =   'mysql:dbname='.$config['database'].';host='.$config['hostname'];
        if (!empty($config['hostport'])) {
            $dsn  .= ';port='.$config['hostport'];
        } elseif (!empty($config['socket'])) {
            $dsn  .= ';unix_socket='.$config['socket'];
        }

        if (!empty($config['charset'])) {
            if (version_compare(PHP_VERSION, '5.3.6', '<')) {
                // PHP5.3.6以下不支持charset设置
                $this->options[\PDO::MYSQL_ATTR_INIT_COMMAND]    =   'SET NAMES '.$config['charset'];
            } else {
                $dsn  .= ';charset='.$config['charset'];
            }
        }
        return $dsn;
    }

    /**
     * 取得数据表的字段信息
     * @access public
     */
    public function getFields($tableName)
    {
        $this->initConnect(true);
        list($tableName) = explode(' ', $tableName);
        if (strpos($tableName, '.')) {
            list($dbName, $tableName) = explode('.', $tableName);
            $sql   = 'SHOW COLUMNS FROM `'.$dbName.'`.`'.$tableName.'`';
        } else {
            $sql   = 'SHOW COLUMNS FROM `'.$tableName.'`';
        }
        
        $result = $this->query($sql);
        $info   =   array();
        if ($result) {
            foreach ($result as $key => $val) {
                if (\PDO::CASE_LOWER != $this->_linkID->getAttribute(\PDO::ATTR_CASE)) {
                    $val = array_change_key_case($val, CASE_LOWER);
                }
                $info[$val['field']] = array(
                    'name'    => $val['field'],
                    'type'    => $val['type'],
                    'notnull' => (bool) ($val['null'] === ''), // not null is empty, null is yes
                    'default' => $val['default'],
                    'primary' => (strtolower($val['key']) == 'pri'),
                    'autoinc' => (strtolower($val['extra']) == 'auto_increment'),
                );
            }
        }
        return $info;
    }

    /**
     * 取得数据库的表信息
     * @access public
     */
    public function getTables($dbName='')
    {
        $sql    = !empty($dbName)?'SHOW TABLES FROM '.$dbName:'SHOW TABLES ';
        $result = $this->query($sql);
        $info   =   array();
        foreach ($result as $key => $val) {
            $info[$key] = current($val);
        }
        return $info;
    }

    /**
     * 字段和表名处理
     * @access protected
     * @param string $key
     * @return string
     */
    protected function parseKey(&$key)
    {
        $key   =  trim($key);
        if (!is_numeric($key) && !preg_match('/[,\'\"\*\(\)`.\s]/', $key)) {
            $key = '`'.$key.'`';
        }
        return $key;
    }

    /**
     * 批量插入记录
     * @access public
     * @param mixed $dataSet 数据集
     * @param array $options 参数表达式
     * @param boolean $replace 是否replace
     * @return false | integer
     */
    public function insertAll($dataSet, $options=array(), $replace=false)
    {
        $values  =  array();
        $this->model  =   $options['model'];
        if (!is_array($dataSet[0])) {
            return false;
        }
        $this->parseBind(!empty($options['bind'])?$options['bind']:array());
        $fields =   array_map(array($this,'parseKey'), array_keys($dataSet[0]));
        foreach ($dataSet as $data) {
            $value   =  array();
            foreach ($data as $key=>$val) {
                if (is_array($val) && 'exp' == $val[0]) {
                    $value[]   =  $val[1];
                } elseif (is_scalar($val)) {
                    if (0===strpos($val, ':') && in_array($val, array_keys($this->bind))) {
                        $value[]   =   $this->parseValue($val);
                    } else {
                        $name       =   count($this->bind);
                        $value[]   =   ':'.$name;
                        $this->bindParam($name, $val);
                    }
                }
            }
            $values[]    = '('.implode(',', $value).')';
        }
        // 兼容数字传入方式
        $replace= (is_numeric($replace) && $replace>0)?true:$replace;
        $sql    =  (true===$replace?'REPLACE':'INSERT').' INTO '.$this->parseTable($options['table']).' ('.implode(',', $fields).') VALUES '.implode(',', $values).$this->parseDuplicate($replace);
        $sql    .= $this->parseComment(!empty($options['comment'])?$options['comment']:'');
        return $this->execute($sql, !empty($options['fetch_sql']) ? true : false);
    }

    /**
     * ON DUPLICATE KEY UPDATE 分析
     * @access protected
     * @param mixed $duplicate
     * @return string
     */
    protected function parseDuplicate($duplicate)
    {
        // 布尔值或空则返回空字符串
        if (is_bool($duplicate) || empty($duplicate)) {
            return '';
        }
        
        if (is_string($duplicate)) {
            // field1,field2 转数组
            $duplicate = explode(',', $duplicate);
        } elseif (is_object($duplicate)) {
            // 对象转数组
            $duplicate = get_class_vars($duplicate);
        }
        $updates                    = array();
        foreach ((array) $duplicate as $key=>$val) {
            if (is_numeric($key)) { // array('field1', 'field2', 'field3') 解析为 ON DUPLICATE KEY UPDATE field1=VALUES(field1), field2=VALUES(field2), field3=VALUES(field3)
                $updates[]          = $this->parseKey($val)."=VALUES(".$this->parseKey($val).")";
            } else {
                if (is_scalar($val)) { // 兼容标量传值方式
                    $val            = array('value', $val);
                }
                if (!isset($val[1])) {
                    continue;
                }
                switch ($val[0]) {
                    case 'exp': // 表达式
                        $updates[]  = $this->parseKey($key)."=($val[1])";
                        break;
                    case 'value': // 值
                    default:
                        $name       = count($this->bind);
                        $updates[]  = $this->parseKey($key)."=:".$name;
                        $this->bindParam($name, $val[1]);
                        break;
                }
            }
        }
        if (empty($updates)) {
            return '';
        }
        return " ON DUPLICATE KEY UPDATE ".join(', ', $updates);
    }
}
